基于DSP的短波通信系統(tǒng)設(shè)計(jì)（射頻單元）

電子通信論文編號(hào):TX079        論文字?jǐn)?shù):22168,頁(yè)數(shù):41

目錄
摘要
ABSTRACT
1 緒論  1
1.1 研究和發(fā)展現(xiàn)狀  1
1.2 射頻及射頻電路的概念  2
1.3 射頻電路設(shè)計(jì)的對(duì)策  3
2 系統(tǒng)總體方案設(shè)計(jì)  7
2.1 射頻發(fā)射器芯片原理與應(yīng)用電路設(shè)計(jì)  7
2.1.1 概述  7
2.1.2 發(fā)射機(jī)的選取  11
2.1.3 主要性能指標(biāo)  11
2.1.4 芯片封裝與引腳  12
2.1.5 內(nèi)部結(jié)構(gòu)與工作原理  13
2.2 功率放大器的設(shè)計(jì)  16
2.2.1 功率放大器總述  16
2.2.2 功率放大器的工作方式  17
2.2.3 放大器的設(shè)計(jì)  19
3 影響射頻電路性能的主要原因分析  21
3.1 信號(hào)的反射及阻抗匹配  21
3.2 射頻部分電路設(shè)計(jì)的一些考慮  22
3.3 射頻部分電路中頻頻率的確定  24
3.4 使用SMD  24
3.5 射頻功放的線性和效率  25
3.6 射頻功放的線性化技術(shù)  27
3.6.1 反饋  27
3.6.2 前饋  28
4 射頻部分電路測(cè)試與結(jié)果  31
結(jié)束語(yǔ)  32

參考文獻(xiàn)  33

摘要
在短波無(wú)線通信系統(tǒng)中，射頻電路是在高頻條件下進(jìn)行工作的，因此，需要利用射頻電路理論去理解射頻電路的工作原理。在高頻條件下的普通的設(shè)計(jì)電路，雜散電容和雜散電感對(duì)電路的影響很大。因此，我采用集成電路的設(shè)計(jì)方法來(lái)避免一些模擬電路的一些缺點(diǎn)。
迅速發(fā)展的射頻集成電路，為從事無(wú)線數(shù)字音頻，數(shù)字視頻數(shù)據(jù)傳輸系統(tǒng)，無(wú)線遙控和遙測(cè)系統(tǒng)，無(wú)線數(shù)據(jù)采集系統(tǒng)，無(wú)線網(wǎng)絡(luò)以及無(wú)線安全防范系統(tǒng)等設(shè)計(jì)，解決無(wú)線應(yīng)用的平靜提供最大的可能。
在整個(gè)短波無(wú)線通信系統(tǒng)的射頻電路中包括，收發(fā)器，中頻帶通濾波器，基帶解調(diào)濾波器，數(shù)據(jù)限幅電平，自動(dòng)增益控制，基準(zhǔn)振蕩器，關(guān)閉功能，I/O接口電路等器件，主要為了實(shí)現(xiàn)短波無(wú)線通信的信號(hào)的輸出以及對(duì)收到的信號(hào)作簡(jiǎn)單的處理，它相當(dāng)于短波無(wú)線通信的前端設(shè)備。

關(guān)鍵詞：射頻電路，PCB設(shè)計(jì)，短波通信

ABSTRACT
In the system of shortwave air communication, the radio frequency circuit carries on work under the high-frequency condition. So, need to utilize the circuit theory of the radio frequency to understand the operation principle of circuit of the radio frequency. The ordinary design circuit under the high-frequency condition , stray electric capacity and impact on circuit of the stray inductance are very great. So, I adopt the integrated circuit design method to avoid some shortcomings of some simulation circuit.
The radio frequency integrated circuit developed rapidly,in order to be engaged in the wireless digital audio frequency, the data transmission system of digital video , wireless remote control and telemetering measurement system, wireless data collecting system, wireless network and wireless safe precaution system,etc. are designed, solve the wireless calmness that uses and offer the greatest possibility.
Include in the radio frequency circuit of the wireless communication system of the whole shortwave, the transceiver, the band-pass filter of intermediate frequency, baseband demodulation wave filter, the amplitude limiting level of the data, gain and control automatically, basic oscillator, close the function, such devices as I/O interface circuit ,etc., in order to realize the output of the signal of shortwave wireless communication and do simple processing to the signal that is received mainly, it is equivalent to the front equipment of shortwave wireless communication.

Key words： Radio frequency circuit ，PCB Design，shortwave communications